Renesas Ethernet AVB controller requires that all data are aligned on 4-byte
boundary. While it's easily achievable for the RX data with the help of
skb_reserve() (we even align on 128-byte boundary as recommended by the manual),
we can't do the same with the TX data, and it always comes unaligned from
the networking core. Originally we solved it an easy way, copying all packet
to a preallocated aligned buffer; however, it's enough to copy only up to
3 first bytes from each packet, doing the transfer using 2 TX descriptors
instead of just 1. Here's an implementation of the new TX algorithm that
significantly reduces the driver's memory requirements.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
net/bridge/br_mdb.c
br_mdb.c conflict was a function call being removed to fix a bug in
'net' but whose signature was changed in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver is written as if it can adapt to a low memory situation allocating
less RX skbs and TX aligned buffers than the respective RX/TX ring sizes. In
reality though the driver would malfunction in this case. Stop being overly
smart and just fail in such situation -- this is achieved by moving the memory
allocation from ravb_ring_format() to ravb_ring_init().
We leave dma_map_single() calls in place but make their failure non-fatal
by marking the corresponding RX descriptors with zero data size which should
prevent DMA to an invalid addresses.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The TCCR.TSRQn bit may get clearead after TCCR gets read, so that TCCR write
would get skipped. We don't need to check this bit before setting.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
First, dma_sync_single_for_cpu() shouldn't have been called in the first place
(it's a streaming DMA API), dma_unmap_single() should have been called instead.
Second, dma_unmap_single() call after handing the buffer to napi_gro_receive()
makes little sense. Moreover desc->dptr might not be valid at this point.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some of the local variable intializers in the driver turned out to be pointless,
kill them.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ethernet AVB device includes the gPTP timer, so we can implement a PTP clock
driver. We're doing that in a separate file, with the main Ethernet driver
calling the PTP driver's [de]initialization and interrupt handler functions.
Unfortunately, the clock seems tightly coupled with the AVB-DMAC, so when that
one leaves the operation mode, we have to unregister the PTP clock... :-(
Based on the original patches by Masaru Nagai.
Signed-off-by: Masaru Nagai <masaru.nagai.vx@renesas.com>
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sergei Shtylyov